The offset printing press has wide application throughout the printing industry. The printing press generally delivers ink from an ink supply through a series of rollers to a roller having the actual image to be imprinted thereon. This image roller, in turn, transfers the ink in the desired pattern to the material being printed on. Many of these rollers are driven by a gear mechanism, usually from only one side of the press, and other rollers are rotated simply by the frictional engagement between that roller and adjacent rollers. Virtually all rollers are mounted on bearings at the ends of the rollers.
Printing quality depends a great deal upon maintaining uniform conditions in the press. One important condition is the temperature of the press, including the temperature of the ink and of the rollers on which the ink is transferred. In almost all printing presses, the gear side runs hotter than the operator side. In addition, when the press is run after a long period of quiescence, the parts of the press will be at room temperature and must be warmed to operating temperature to provide consistent printing.
In certain presses, a water coolant flow is utilized to cool various portions of the press and attempt to maintain a uniform temperature within the press. However, it has been found that water cooling has not been totally effective at providing a consistent and uniform temperature within the critical components of the press. Therefore, a need exists to better control the temperature of these critical components.